Mosquito Proboscis (Figure 1) THE MOSQUITO LIFE CYCLE ABOUT CONTRA COSTA INSECTS Mosquitoes have four distinct developmental stages: MOSQUITO & VECTOR egg, larva, pupa and adult. The average time a mosquito takes to go from egg to adult is five to CONTROL DISTRICT COMMONLY Photo by Sean McCann by Photo seven days. Mosquitoes require water to complete Protecting Public Health Since 1927 their life cycle. Prevent mosquitoes from breeding by Early in the 1900s, Northern California suffered MISTAKEN FOR eliminating or managing standing water. through epidemics of encephalitis and malaria, and severe outbreaks of saltwater mosquitoes. At times, MOSQUITOES EGG RAFT parts of Contra Costa County were considered Most mosquitoes lay egg rafts uninhabitable resulting in the closure of waterfront that float on the water. Each areas and schools during peak mosquito seasons. raft contains up to 200 eggs. Recreational areas were abandoned and Realtors had trouble selling homes. The general economy Within a few days the eggs suffered. As a result, residents established the Contra hatch into larvae. Mosquito Costa Mosquito Abatement District which began egg rafts are the size of a grain service in 1927. of rice. Today, the Contra Costa Mosquito and Vector LARVA Control District continues to protect public health The larva or ÒwigglerÓ comes with environmentally sound techniques, reliable and to the surface to breathe efficient services, as well as programs to combat Contra Costa County is home to 23 species of through a tube called a emerging diseases, all while preserving and/or mosquitoes. There are also several types of insects siphon and feeds on bacteria enhancing the environment. located throughout the county that many people in the water. In a matter of perceive as a mosquito, but actually are different days, the larva will molt (shed FREE Services for Photo Alvesgaspar by species of insects. Please note: we do not provide its skin) four times. On the Contra Costa County Residents services for insects other than mosquitoes, fourth molt it will change into MOSQUITOES TICKS yellowjackets, and bees. a pupa. Inspection and control Tick identification Mosquito adults are small, delicate, two-winged flies. MOSQUITOFISH RATS AND MICE At first you might mistake them for the widely PUPA Free for residential ponds Inspection and advice distributed, nonbiting midges. However, female The pupa or ÒtumblerÓ YELLOWJACKETS mosquitoes differ from similar insects because of their cannot eat. It breathes AND BEES SKUNKS long, slender proboscis (proh-bos-is,-kis), a tubular through two tubes on its back. Ground-nest and Inspection swarm control and assistance feeding organ adapted for piercing skin and sucking The adult mosquito grows blood (see Figure 1, above). They need blood in order inside the pupal casing and to produce eggs. within a few days, when it is PUBLIC EDUCATION Literature and presentations fully developed, it will split If you were to view a mosquito with a magnifying the casing and emerge to glass, you would see another characteristic that Rev. 3/17 distinguishes mosquitoes from closely related complete the life cycle, fliesÐsmall scales cover their long, slender wings. Male or metamorphosis, of the mosquitoes also have scale-covered wings, but they mosquito. use their proboscises, or ÕbeaksÕ, only for sucking plant juices and other sources of sugar rather than blood - ADULT they do not bite people or other animals. The newly emerged adult rests Female mosquitoes bite and take in a blood on the surface of the water meal using its proboscis (see Figure 1, above). until it is strong enough to fly away. Contra Costa Mosquito & Vector Control District The wings of a mosquito are as long or longer 155 Mason Circle ¥ Concord, CA 94520 than its body. (925) 771-6172 office ¥ (925) 685-0266 fax Mosquitoes usually lay eggs in water. www.ContraCostaMosquito.com INSECTS COMMONLY MISTAKEN FOR MOSQUITOES

CHIRONOMID BITING MIDGES CRANE FLIES FUNGUS GNAT MIDGES (culicoides) (tipulidae) ADULTS (chironomidae) or Ôno-see-ums,Õ are minute also known as mosquito (anisopodidae) are the most common type insects known for being hawks and mosquito- are common in shaded, of midge and are often vicious daytime biters. eaters, are delicate insects wooded areas. Different seen swarming in open Coming primarily from and fly poorly. They vary in species range in size from spaces, particularly near damp sandy clay or mud, size from ¼th of an inch to tiny to larger than bodies of water. When they are often found close as large as 1½ inches. The mosquitoes. Under a populations become large, to their source (rivers, lakes larger varieties are often magnifying glass, most they can be seen resting and seashores) due to mistaken as Ôgiant species can be seen to on walls and screens of limited flight capacity. mosquitoesÕ but adults are have prominent spines on buildings. Midges can Despite their name and completely harmless and their legs which are absent be distinguished from small size (some can pass do not bite. They are in mosquitoes. They lack a mosquitoes: they donÕt through standard window attracted to lights and often biting proboscis and their have a biting proboscis and lack scales on their wings. Midge screens), they are easily visible to the naked eye. congregate around porch lights. Despite their common wings donÕt have scales. larvae develop in lakes, ponds and streams. names, they do not feed on mosquitoes; in fact adults of They are uncommon in Contra Costa County, but in some most species do not feed at all. The adult crane fly (pictured They are found in foliage in or near damp places and are Some species are extremely tolerant of polluted conditions parts of the world they are a significant pest capable of above) only lives for about three days. The larvae live in mud sometimes seen in small swarms. They are attracted to lights, and may be found in enormous numbers in and around transmitting diseases of cattle and other livestock. and feed on decaying vegetation and other organic sometimes in large numbers, and can be found indoors, sewage treatment plants. They typically live on or in the material. particularly in house plants that are overwatered and/or mud, unlike mosquito larvae that float at the surface of the have poor drainage. The larvae feed on fungi and mold in water. The larvae of many species contain hemoglobin OWL MIDGES the soil. Adults are harmless and cannot bite. (similar to whatÕs found in our blood) hence the common (psychodidae) MAYFLIES name ÔbloodwormsÕ. Mass hatching can occur and the also known as drain flies or (ephemeroptera) spontaneous appearance of swarms of adults can be very sewer flies, are small, hairy are found commonly near DANCE FLIES noticeable in the spring and summer. Adults live for about flies that can move about creeks, flood control (empididae) a week. very nimbly, but are weak channels and other water are gnat-like insects

Photo by Sanjay Acharya by Photo fliers. They lack a proboscis, sources. Despite their that are named because but do have scales and common name, they are of their noticeable vertical DIXID MIDGE hairs on their rounded, not considered true flies movement or ÔdancingÕ Photo by André Karwath André by Photo (dixidae) paddle-shaped wings. because they have four behavior. These ÔdancingÕ is commonly found around wings rather than two. Their swarms consist mostly of moist areas with abundant The larvae are aquatic or larvae are found in most males who are competing vegetation. Typically at semi-aquatic and are very aquatic habitats and prefer to mate with passing dusk, dixid midges can be common in sewers and to live in running water. females. They are generally seen swarming along the drains where they feed on slime and debris. The larvae are larger and heavier edges of streams and lakes. able to live in soapy water. When found indoors they are a Adult mayflies have large triangular front wings with many bodied (more fly-like) Adults live less than a week good indicator of a leak in a shower/bath, sink, or laundry cross veins. The wings are held upright over the thorax. They than mosquitoes. and are incapable of biting. drain. Cleaning out sink and tub drains and traps can reduce also have long filaments or ÔtailsÕ at the end of their body. They lack a proboscis and or eliminate indoor nuisance problems. Mayflies are an important source of food for trout and other Spring swarms are seen in open, sunny places like clearings in wing scales. game fish. At certain times of the year huge numbers may the woods. They prey on other insects including mosquitoes emerge simultaneously from particular bodies of water. They and are therefore considered beneficial insects. Larvae are found growing are attracted to lights and the resultant large swarms may at the surface of slow-moving water, are wormlike and swim alarm some people. Adult mayflies are short-lived, do not by bending their bodies in an easily identifiable u-shape. feed and survive just a couple of days. They feed mainly on algae.